This article examines the determinants of public opinion on differentiated integration (DI) in the European Union (EU). Specifically, it tests whether citizen attitudes are informed by the national experience of opt‐outs and exclusions from full participation in EU policies. The study...

This report examines the dynamics of differentiated integration. In particular, it studies whether differentiated integration is a path-dependent process, in which earlier differentiation increases the likelihood of additional differentiation in the future. In a set of analyses on the EU’s...

Differentiation has become a salient feature of European integration. Yet systematic empirical evidence is lacking about its origins, duration and variation across countries and policies. This article provides such evidence from a new data set on differentiation in European Union treaty law. In...

In order to capitalize on its increasing legislative powers, the European Parliament (EP) has had to specialize internally. The scholarly literature has predominantly studied the structural manifestations of specialization, such as the allocation of committee seats among parliamentarians. This...

This paper reports a descriptive analysis of the historical development and the modes of differentiated integration in the treaties and legislation of the European Union. Whereas the number of differentiations has increased in the course of European integration, it has remained stationary...